brass ring

A chance to achieve wealth or success; a prize or reward. For example, “As a businessman he let the brass ring go by too many times. And it got him.” This quotation from the Boston Globe (July 31, 1995) refers to an executive who was forced to resign. The term comes from the practice of giving a free ride to the person who succeeded in picking a ring out of a box while riding a merry-go-round.
[ ; late 1800s
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